the office, he (to read) at home. 7. I (not to see) you for a while! You (to be) busy at work? - I (to have) an awful week, you (to know). 8. What he (to do) at ten o'clock last night? - He (not to do) anything really. He just (to look) at some magazines. 9. We (to have) rather a difficult time at the moment. - I (to be) sorry to hear that. 10. Something awful (to happen). Her little daughter (to swallow) acoin. 11. She (to ask) me if I (to see) her backpack. 12. After the boys (to do) all the work, they (to go) to the theatre.

1. I have not seen you for a while! (Present Perfect, так как действие началось в прошлом и продолжается до настоящего времени) You are busy at work? (Present Simple, так как вопрос о текущем состоянии) I have had an awful week, you know. (Present Perfect и Present Simple)
2. What was he doing at ten o'clock last night? (Past Continuous, так как спрашивают о процессе в определенное время в прошлом) He did not do anything really. (Past Simple, так как действие произошло в прошлом) He just looked at some magazines. (Past Simple, так как действие произошло в прошлом)
3. We are having rather a difficult time at the moment. (Present Continuous, так как действие происходит сейчас) I am sorry to hear that. (Present Simple)
4. Something awful is happening. (Present Continuous, так как действие происходит сейчас) Her little daughter swallowed a coin. (Past Simple, так как действие произошло в прошлом)
5. She is asking me if I see her backpack. (Present Continuous и Present Simple, так как действие происходит сейчас и спрашивают о текущем состоянии)
6. After the boys do all the work, they will go to the theatre. (Present Simple и Future Simple, так как одно действие произойдет после другого)

Ответ: have not seen, are, have had, know, was...doing, did not do, looked, are having, am, is happening, swallowed, is asking, see, do, will go